cvs-fast-export analyzes a collection of RCS files in a CVS repository (or outside of one) and, when possible, emits an equivalent history in the form of a fast-import stream. Not all possible histories can be rendered this way; the program tries to emit useful warnings when it can't. The program can also produce a visualization of the resulting commit DAG in the DOT format handled by the graphviz suite. The package also includes cvssync, a tool for mirroring masters from remote CVS hosts.
Cil is an easy-to-use command-line driven distributed issue tracker. Using Git as it's storage backend, the power of a distributed version control system can be harnessed to enhance and provide powerful features. Cil saves the issues, comments, and attachments locally in plain-text for ease of use and easy accessibility.
gitolite is an access control layer on top of git. It allows you to setup git hosting on a central server, and have multiple "virtual" users (i.e., not "Unix" users) access multiple git repositories, with fine grained access control (read control at the repo level granularity, write control at branch/tag/file/dir level). It has several other features, comprehensive documentation, does not require root permissions, and does not depend on anything except git, Perl 5.8 or later, and any POSIX shell.
RepoManager offers a minimalistic approach to Web-based management of version control system repositories. Its goal is to simplify effective handling of repository permissions for a large number of users. Using RepoManager, users themselves are able to grant others permissions to use their repositories whenever they want.
git-flow Python Edition is a a pure Python implementation of git-flow. All sub-commands share a common back-end to ensure features behave the same, whatever branch-type they are working on. New workflow behavior can also be added easily by simply sub-classing existing ones. It also includes a comprehensive unit test suite, decent man pages, and HTML docs.
Gerrit is a Web-based code review system, facilitating online code reviews for projects using the Git version control system. Gerrit makes reviews easier by showing changes in a side-by-side display and allowing inline comments to be added by any reviewer. Gerrit simplifies Git-based project maintainership by permitting any authorized user to submit changes to the master Git repository, rather than requiring all approved changes to be merged by hand by the project maintainer. This functionality enables a more centralized usage of Git.